One of methods for making hair look beautiful is to enhance luster of the hair. In order to realize enhanced luster of hair, there have been used various methods such as a method of enhancing smoothness on a surface of hair to suppress light scattering thereon, and a method of improving the manageability of a hair bundle to form a large reflection surface thereon and generate a sharp reflected light therefrom.
Other effective methods for making hair look beautiful include the method of rendering a color of hair clear or vivid, for example, by applying a hair color, etc., to the hair to add a fresh bright color thereto (coloring, etc.). As a result of the coloring, etc., a youthful look or vivid look is imparted to persons, leading to a personal image-change. In the coloring method, etc., although the color of hair may be changed quite differently, an inherent natural color of the hair itself is not caused to look clear or vivid. Further, the hair dyed by the coloring method tends to be undesirably discolored by degradation and deterioration of dyes owing to UV radiation and oxidation, or by elution of the dyes owing to repeated treatments with shampoo or conditioner.
To solve the problems, there is a generally known method of blending an ultraviolet absorber, an antioxidant or a silicone compound in the shampoo or conditioner to inhibit the discoloration of hair. For example, it has been reported that hair dyed by coloring is treated with a conditioner blended with an amino-modified silicone to prevent discoloration of the hair due to shampooing (refer to “JOURNAL OF COSMETIC SCIENCE, 2003 ANNUAL SCIENTIFIC MEETING”, p. 130). Also, it has been reported that silicones are blended in a shampoo to inhibit discoloration of colored hair due to shampooing (refer to U.S. Pat. No. 5,609,861 and US 2003/0198615A). These methods are effective to reduce the speed of discoloration of colored hair, but do not serve for allowing the color of the hair to positively look clear or vivid.
Also, there are known shampoos or conditioners directly blended with dyes or pigments (refer to PCT pamphlets Nos. WO 03/055457, WO 01/78670 and WO 01/78671). These shampoos or conditioners are effective to render the color of hair vaguely clear or vivid and compensate for the discoloration of colored hair, but do not serve for allowing natural color of the hair or a color of the hair dyed to look natural and clear or vivid.